As the advancement of electronic industry and wider application, the computation performance of electronic devices has been largely upgraded. The currently available electronic devices are characterized in their compact volume, low profile and light weight. To meet these requirements, all elements of the electronic devices must also have largely reduced in dimension, allowing the density of Integrated circuits (ICs) is higher and higher. As number the computing elements is increasing, the computation units of the electronic device at high speed also produce much more heat during operation thereof, such that the heat it generates can burn out the entire electronic elements if the heat cannot be dissipated quickly.
To lower the temperature of the heated electronic elements during operation, a water cooling device is available in the market. The water cooling device includes a water cooling structure, two water guiding tubes, and a water pump. The two water guiding tubes are connected to the water pump and a water head, such that a cooling water, or called working fluid, is flowed back and forth in the water cooling device by an operation of the water pump to quickly remove the heat produced by the electronic elements. Please refer to FIG. 1, which is a perspective view of a conventional water cooling device 1. As shown, the water cooling device 1 includes a plurality of flexible heat radiation fins 11, a plurality of flat pipes 12, and two water reservoirs 13 provided on two sides thereof. The flat pipes 12 are paralleled arranged and the heat radiation fins 11 are located in between, such that the flat pipes 12 can correspondingly connected to the heat radiation fins 11 at junctions on a blended outer sides of the heat radiation fins 11 and an outer side of the flat pipes 12 by welding. In other words, the heat radiation fins 11 are connected at several points to the flat pipes 12. Also, the water reservoirs 13 are connected to both the heat radiation fins 11 and the flat pipes 12 by welding to form the water cooling device 1. Each the water reservoirs 13 has a water inlet 131 and a water outlet 132, which are correspondingly connected to two water guiding tubes, respectively (not shown).
The heat radiation fins 11 are connected to the flat pipes 12 by welding, but they are two independent members and not integrally formed, causing heat produced by the electronic elements cannot be effectively transferred from the cooling water to the heat radiation fins 11, and further a thermal resistance occurs when the heat is transferred from the flat pipes 12 to the heat radiation fins 11. It means that the heat cannot be effectively transferred from the flat pipes 12 to the heat radiation fins 11 after the flat pipes 12 absorbs the heat from the cooling water, so as to lower the whole heat dissipation efficiency. Moreover, the flat pipes 12 and the heat radiation fins 11 are connected to each other only at several points on the two outer sides thereof, causing the flexible heat radiation fins 11 to have a weak central portion, which is easy to be damaged or deformed, and accordingly to have adverse heat transfer effect.
Moreover, the conventional water cooling device 1 is composed of three independent members, meaning it is complicated and takes too much time to assemble the conventional cooling system due to many components thereof with water leaking risks.